Patterning mechanism for multi-feed circular knitting machines

ABSTRACT

Pattern jacks in a multi-feed circular knitting machine are accommodated in a cylinder co-axial with but of a larger diameter than the needle cylinder. Jack butts are set out in diagonal lines. At each feed there is a slotted block housing a vertical bank of superimposed pairs of jack selector tuck and knit slides having cam faces upwardly sloping to two different extents heightwise. Springs urge selector slides into operative positions, slides being selectively held withdrawn clear of jack butts against the biassing influence. Movements of jacks imparted by slides are less than sufficient to raise corresponding needles to heights required. Thus movement transmitting and amplifying levers are provided between the jacks and the needles. In each slotted block is a removable toothed programme comb having some teeth reduced in length and others broken away, according to pattern. Teeth act on projections on slides to hold them back. Jacks are either not raised or are raised to one of two heights to cause needles to miss, tuck or knit depending on the layout of teeth, half teeth and gaps on and in the programme comb.

United States Patent [191 Canderton et al.

51 July 23, 1974 PATTERNING MECHANISM FOR MULTI-FEED CIRCULAR KNITTING MACHINES [75] Inventors: Norman Victor Candertom-Oadby;

Walter Goadby, Evington, both of England [73] Assignee: Camber International (England) Limited, Leicester, England [22] Filed: Mar. 5, 1973 [21] Appl. No.: 338,063

[30] Foreign Application Priority Data Mar. 11,1972 Great Britain 11496/72 [52] US. Cl 66/50 R [51] Int. Cl D04b 15/68 [58] Field of Search 66/50 R, 50 B, 25

[56] References Cited UNITED STATES PATENTS 3,283,540 11/1966 Levin 66/50 R X 3,641,787 2/1972 'Robottom 66/50 R 3,739,601 6/1973 Plath 66/50 B 3,740,971 6/1973 Font 66/50 B 3,793,850 2/1974 Wills-Moren et a1. ..-66/50 R I FOREIGN PATENTS OR APPLICATIONS 508,304 l/l952 Belgium 66/50 B 1,212,574 11/1970 Great Britain 66/50 B 1,240,761 7/1971 Great Britain 66/50 R OTHER PUBLICATIONS The Hosiery Trade Journal, Oct. 1972, Vol. 79, No.

946, pp. 86 & 87.

Primary ExaminerWm. Carter Reynolds Attorney, Agent, or Firm-Larson, Taylor & Hinds [57] ABSTRACT Pattern jacks in a multi-feed circular knitting machine are accommodated in a cylinder c o-axial with but of a larger diameter than the needle cylinder. Jack butts are set out in diagonal lines. At each feed there is a slotted block housing a vertical bank of superimposed pairs of jack selector tuck and knit slides having cam faces upwardly sloping to two different extents heightwise. Springs urge selector slides into operative positions, slides being selectively held withdrawn clear of jack butts against the biassing influence. Movements of jacks imparted by slides are less than sufficient to raise corresponding needles to heights required. Thus movement transmitting and amplifying levers are provided between the jacks and the needles.

In each slotted block is a removable toothed programme comb having some teeth reduced in length and others broken away, according to pattern. Teeth act on projections on slides to hold them back. Jacks are either not raised or are raised to one of two heights to cause needles to miss, tuck or knit depending on the layout of teeth, half teeth and gaps on and in the programme comb.

15 Claims, 9Drawing Figures 1 PATTERNING MECHANISM FOR MULTI-FEED CIRCULAR KNITTING MACHINES This invention relates to circular multi-feed knitting machines, and has reference particularly to such machines of the kind comprising a needle cylinder axially tricked to receive individually operable knitting needles, and a set of suitably carried corresponding pattern jacks furnished with patterning butts adapted to be acted upon selectively by prearranged jack selector slides disposed in vertical banks usually one bank in advance of each feed.

In a circular knitting machine of this kind the selective action of. the pattern jacks is for the purpose of exercising such selective individual control over the needles that whilst predetermined ones are permitted to remain down and non-knit, others are raised, e.g. either to clearing height so that they knit, or to an intermediate height so that they tuck, all according to knitting requirements.

The patterning butts on the pattern jacks, one butt per jack in a machine of the kind concerned are commonly so disposed in a multiplicity of superimposed planes as to enable the butts in any one horizontal plane to be well spaced apart circumferentially: in such an arrangement, the butts on successive jacks are so relatively offset laterally in the superimposed planes as to be in echelon formation rightaround the machine, -i.e. to present circumferentially spaced and parallel lines of butts extending diagonally, the lateral offsetting corresponding, of course, with the pitch of the jacks circumferentially of the machine.

It is, however, also possible for the diagonal lines of butts, instead of extending all in the same direction parallel to one another, to extend alternately in opposite directions suchwise as to meet in a succession of VS. Or a combination of diagonal lines and VS may be adopted.

It is primarily the intention that the invention shall be applied to a circular multi-feed knitting machine of the rotary needle cylinder type, in which instance the individuallyoperable needles and their actuating pattern jacks move round with the knitting head, whereas the banks of prearranged jack selector slides are associated or combined with the stationary cam box or shell surrounding the needle cylinder.

There is, however, no limitation in this respect since it would alternatively be'possible to apply the invention to a multi-feed machine of the'stationary needle'cylinder type, in which case the banks of prearranged jack selector slides would be required to revolve together with the annular cam box or shell.

The object of the present inventionis to provide, in a multi-feed circular knitting machine of the kind herein referred to, a generally improved arrangement of the patterning mechanism designed'substantially to increase the patterning scope of themachine whilst at the same time enabling the axial dimension of the needle cylinder to be keptto-a minimum.

The patterning mechanism according to this invention, comprises, in combinationz pattern jacks which are accommodated in tricks formedina'separate jack cylinder which is-co-axialwith, but of a larger diameter than, the needle cylinder,the patterning butts on these jacks being set out in diagonal lines as aforesaid but with the vertical pitch of said butts reduced to such an extent that liftingmovements imparted to'the pattern sponding needles to the heights required; means for transmitting to the needles and simultaneously amplify-v ing the lifting movements imparted to the pattern jacks by the slides; slotted blocks each for accommodation of one of the vertical banks of jack-selector slides in each of which blocks the selector slides are arranged in superimposed pairs respectively opposite the planes of pattern jack butts, with the two slides of each pair disposed side by side and constituting tuck and knit slides with operative noses having cam faces upwardly sloping to respectively different extents heightwise; springs within the slotted blocks urging the slides into their selected positions but against the biassing influence of which the slides are withdrawable to inoperative positions clear of the pattern jack butts in the relevant planes; and, in association with each slotted block, a removable toothed programme comb having predetermined ones of its teeth reduced in length and others broken off according to pattern requirements, the arrangementbeing such that depending on whether a full length tooth, a tooth of reduced length or a gap in the comb produced by breaking-off a tooth is presented adjacent to abutments on a pair of jack selector slides, the

corresponding pattern jacks with patterning butts at that level will either not be raised, or only partially raised or fully raised to cause the relevant needles to miss, tuck or knit respectively.

Thus, as will be appreciated, each slotted block is itself in the nature of a mechanical patterning unit of a kind which, when once set by the insertion of a programme comb to produce a desired pattern, requires to be re-set manually by removal of the comb and insertion of a fresh comb before another pattern can be produced. In other words, the programme comb is, in effect, a pattern key the predetermined form of which may vary practically infinitely depending on which teeth are reduced in length and/or which are broken off. In any event, the slides are not themselves selectively operated under control, and when once the pairs of knit and tuck slides in any one of the slotted blocks have been fixed in the required positions, by insertion of a programme comb, they remain in these positions for a run of theknitting machine and can only be changed by a change in the comb.

The idea is that the upwardly inclined cam face of each tuckslideshall be adapted, by engagement with pattern jack butts at the relevant level, to lift deired pattern jacks only sufficiently far tocause corresponding needles, through the medium of the movementtransmitting and amplifying means to be raised to tucking height, whereas the upwardly inclined cam face of each knit slide, together with the cam face of the companion tuck slide, lifts pattern jacks to an extent sufficiently far to cause corrsponding-needles to be raised to clearing height and to knit.

Preferably, the verticalpitch of the patterning butts on successive pattern jacks is such that the lower edge of the butt on any one jack is spaced vertically from the corresponding edge of the butt on the next jack a distance equal only to the overall vertical dimension of a single butt. In this preferred case, therefore, an individual jack can only be liftedbyany-one slide a distance equivalent to the vertical pitch of the butts.

The advantage of the inventionis that by reducing this vertical dimension to a minimum, compatible with the practical minimum thickness of the jack selector slides, the number of such slides in each vertical bank, i.e. in each slotted block, can be a maximum calculated to maximize the patterning scope of the machine. And yet at the same time not only can the axial dimension of the separate pattern jack cylinder be kept within an economical limit, but an economically produced needle cylinder of comparatively small length can be used.

In order that the invention may be more clearly understood and readily'carried into practical effect, a specific constructional example thereof will now be described with reference to the accompanying drawings, wherein, p

FIG. 1 is a general perspective view illustrating a few of the pattern jacks in the preferred form of the improved patterning mechanism as applied to a multifeed circular knitting machine of the rotary needle cylinder type, all but one of said jacks being shown in its lowered position, and the nose portions of one pair of jack selector slides, depicted in their forward positions, having just raised the relevant jack to knit height so that the corresponding latch needle is at clearing height having been raised to that position through the medium of the corresponding movement-transmitting and amplifying lever,

FIG. 2 is a plan view showing a few of the manuallysettable selection blocks provided around the machine one block per feed,

FIG. 3 is a vertical sectional view, taken on the broken line III III of FIG. 4, through one slotted selection block, the needle cylinder and the separate jack cylinder, the remainder of the knitting head of the machine being shown in chain lines, and a pattern jack, which has just been elevated by a slide, being shown in relation to the corresponding needle and the intermediate movement-transmitting and amplifying lever,

FIG. 4 is an inner end view of two adjacent selection block units'as seen-in the direction of the arrow IV in FIG. 5 is an outer end view as seen in the direction of the arrow V in FIG. 3, showing (in dotted lines) a programme comb which is inserted into position in the selection block fully shown in this figure,

FIG; 6 is a fragmentary portion of a programme comb having thereon both full length and half teeth and having therein a gap produced by the omission of two teeth,

FIG. 7 is a detail plan view of one of the laminates of a selection block showing the tuck slide operative and the companion knit slide withdrawn to its inoperative position,

FIG. 8 is a similar detail plan view depicting both slides of the pair withdrawn, i.e. held out, and

FIG. 9 is yet another similar plan view showing both of the slides in their forward operative positions.

Like parts are designated by similar reference characters throughout the drawings.

Referring first to FIG, 3 it will be seen that the illustrated multi-feed circular knitting machine comprises a rotary needle cylinder 10 which is axially tricked at 10a to receive individually slidable latch needles such as 11. Each such needle is provided with not only a butt 1112 at its lower end for a purpose hereinafter to be described, but also with an upper needle-operating butt 11a adapted to be acted upon by knitting cams housed in a stationary annular cam box or shell surrounding the needle cylinder 10. Pattern jacks 13, corresponding in number to the number of needles 11, are similarly accommodated intricks 14a formed in a separate jack cylinder 14 which is co-axial with, but of larger diameter than, the needle cylinder 10. The jack cylinder 14, which revolves together with the needle cylinder 10, is driven by a toothed gear plate 15. This plate is accommodated within a fixed plate 16. Also located within the last mentioned plate, above the rotary toothed gear plate 15, is a fixed bed plate 17 upon which are fixedly mounted the aforementioned slotted blocks 18 (see FIG. 2) each for accommodation of a vertical-bank of superimposed pairs of jack selector slides 19, 20.

Each pattern jack 13 has thereon a single patterning butt l3a, the said butts on successive jacks being so relatively offset laterally in a multiplicity of superimposed planes as to be in echelon formation right around the machine, i.e. in parallel, diagonally extending linesL'as shown in FIG. 1.

The jack selector slides 19, 20 are accordingly arranged in superimposed pairs respectively opposite the superimposed-horizontal planes of patterning butts 13a on the pattern jacks 13. The two slides 19,-'20 of each pair are disposed closely side by side, as illustrated more clearlyin FIGS. 7, 8 and 9, and constitute tuck and knit slides with operative noses having cam faces 19a, 20a upwardly sloping to respectively different extents heightwise. Springs 21 within the slotted blocks 18 urge the companion slides 19, 20 into their selected positions, and it is against the biassing influence of these springs that theslides 19, 20 are withdrawable to inoperative positions clear of the patterning butts 13a in the relevant planes.

It will be appreciated from the foregoing description that in the preferred embodiment of the invention illustrated in the drawings, the butts 13a on the pattern jacks 13 are set out in a multiplicity of superimposed horizontal planes equally spaced apart heightwise a distance d (FIG. 3) measured from the bottom edge of one butt to the bottom edge of the next adjacent butt, equivalent to the vertical pitch 'of the butts 13a.

Advantageously, these butts 13a on the pattern jacks may be of saw-tooth form, having, as shown, horizontal lower edges and upper edges which incline downwardly and outwardly from the stems of the jacks. By virtue of this particular shaping of the butts 13a, the inner operative cam-like noses 19a, 20a of the slides 19, 20 are enabled to be inserted beneath the horizontal lower edges of butts and well into the spaces between butts as shown in FIG. 1.

Simple, radially extending movement-transmitting and amplifying levers 22 are provided, as shown in FIGS. 2 and 3, between upper rounded ends 13b of the pattern jacks 13 in the separate jack cylinder 14 and the lower butts 11b of the needles in the-needle cylinder. In fact, the inner end of each of these levers 22 is recessed at 22a to receive the lower butt 1 1b of the corresponding needle. The levers 22 thus extend across the annular space S between the two co-axial cylinders 10 and 14 of respectively different diameters and are located beneath the annular cam box or shell surrounding the needle cylinder 10. The outer end of each of the movement-transmitting and amplifying levers 22 is formed with a near-circular fulcrum 22b which is seated in a suitably formed ring 23 combined with the upper end of the pattern jack cylinder 14. To enable them to avoid interference with the jack cylinder 14,

the pivoted levers 22 are of upwardly arched form. In any event, the upper rounded ends 13b of the pattern jacks 13 act upon the lower edges of the levers 22 at carefully predetermined points fairly close to the nearcircular fulcra 22b so that comparatively small lifting movements of the jacks l3 imparted by jack selector slides 19 or are magnified into substantially greater heightwise movements (such as a! FIG. 3) of the inner ends of the said levers.

Of each pair of jack selector slides 19, 20 the tuck slide 19 must be enabled to move radially into its operative position, under its biassing spring 21, independently of the companion knit slide 20 whilst the latter is held back in its inoperative position as depicted in FIG. 7. On the other hand,whenever the knit slide 20 of a pair is permitted to move radially into its operative position it must, for safety reasons, cause the compan- 7 ion tuck slide 19 to move together with it as seen in FIG. 9. Conversely, any knit slide 20can be withdrawn into its inoperative position independently of its companion tuck slide 19 which latter can be left operative (FIG. 7); but with both slides operative (as in FIG. 9), withdrawal of the tuck slide to its inoperative position must, for safety reasons, also result in automatic withdrawal of the knit slide. To achieve these requirements,

each tuck slide 19 is provided with a lateral projection 19b arranged to move within a suitably elongated recess 20b formed in the adjacent side of the companion knit slide 20. In such an arrangement the lateral projection abuts against the forward ends of the tail portions T? of both slides 19 and 20.

In the illustrated embodiment of the invention, at least the major portions of the jack selector slides 19, 20 are disposed in superimposed horizontal planes in which instance the cam-like noses at the inner ends of the slides themselves require to have upwardly inclined butt-engaging faces 19a, 20a. Alternatively, however, the pairs of slides 19,20 of the vertical bank in each slotted block 18 may themselves be in parallel inclined planes with respect to the horizontal so that their operative noses can be in these same planes the angle of inclination being such as to impart to the jacks the required relatively small extents of lift.

Apart from the complementary form of their operative cam-like noses, the jack selector slides of each pair 19, 20 may generally be opposite handed, viz. one lefthand and the other right-hand as shown. In any event, each slide has a main front portion FP which, together with its cam-like operative nose 19a or 20a, protrudes through the front of the relevant slotted block 18, and a relatively slim rear or tail portion T? which protrudes rearwardly through the back of the block.

Although it would, within-the broad scope of the invention, be possible for the main front and the rear or tail portions FF and TP of each slide 19 or 20 to be fashioned in one piece from the same material, it is preferred, on the ground of economy, to make the main front portion FP separately from and in a harder and more expensive material than the rear or tail portion TP and to rigidly connect together the two portions, e.g. by complementarily interengageable formations such as those shown in plan in FIGS. 7, 8 and 9.

In association with each slotted block 18, there is provided a removable toothed programme comb 24 which, although it initially had a full complement of unbroken teeth such as 24a, has predetermined ones of these teeth reduced in length, as at 24b in FIG. 6, and

7 others wholly broken off to leave a gap g according to pattern requirements. Depending on whether a full length tooth 240, a tooth 24b of reduced length or a gap g in the comb 24 produced bywholly breaking off a tooth is presented to a pair of jack selector slides 19, 20, the corresponding pattern jacks 13 at that level will either not be raised, or.only partially raised or fully raised to cause the relevant needles 11 to miss, tuck or knit respectively.

To enable each of the slides 19 and 20 to be held back in its withdrawn position (if required by the pattern) by a tooth 24a or 24b at the relevant height on an inserted programme comb 24,the rear or tail portion T? of the slide is provided with a rigid abutment 25 for contact, at its leading end, with the backof the tooth. For instance, and as shown in FIGS. 3, 7, 8 and 9, an outer margin of the rear or tail portion TP may be slit longitudinally and bent downwardly to provide the rigid abutment 25. In such a case, if there is no tooth on the programme comb 24 at the level of the downwardly bent abutment 25 on any one slide the latter is permitted, under the action of its spring 21, to move forwardly into its operative butt-engaging position, the said abutment idly entering and being accommodated within a recess 26 formed for the purpose in the relevant'slotted block 18 (see FIG. 3).

The rear or tail portions TP of all of the pairs of tuck and knit slides 19 and 20 are formed, e.g. recessed as at 27, for reception of a tool of any apropriate character by means of which all of the superimposed pairs of slides in any one slotted block 18 can be simultaneously withdrawn against the action of their springs 21 to their inoperative positions and held there whilst a programme comb 24 is inserted into position at the back of the block immediately in front of the rigid abutment 25 on the slides. After insertion of the comb 24 and removal of the tool, all those slides whose abutments 25 are opposite gaps g in the comb are enabled to spring forward into their operative positions, whereas the remaining slides having abutments opposite teeth 240 or parts of teeth, 24b on the comb are as a matter of course held back in their inoperative positrons.

As previously mentioned, each programme comb initially has thereon a full complement of full length teeth 24a corresponding in number to the number of pairs of slides 19, 20 in the corresponding slotted block 18, each tooth being notched at its root and substantially half way along its length to facilitate easy breakage. Thus, to prepare a comb 24 in accordance with the required pattern, some of the full length teeth 24a are wholly broken off at their roots, others are left intact and yet others are broken away at their mid-points to leave half teeth 24b. Wherever a tooth 24a is left wholly intact, as in FIG. 8, the tuck and the knit slides 19 and 20 of the relevant pair are both held back in their inoperative positions to cause appropriate needles to miss; wherever a gap 3 is produced in the comb by wholly breaking away a tooth 240, both slides 19 and 20 of a pair are permitted to move into their forward operative positions, as in FIG. 9; if only the outer half of a tooth is broken away, the remaining half, 24b holds back a knit slide 20 whilst only the companion tuck slide 19 moves into its operative position to cause appropriate needles to tuck.

The vertical edge of each programme comb 24 remote from the teeth has thereon, as shown in FIG. 5,

a flat protuberance 240 which can be taken between thumb and fingers both when inserting the comb into position .and when removing it for replacement by a fresh comb.

Each slotted block 18 accommodating a vertical bank of pairs of the tuck and knit slides 19, 20 is interposed between and rigidly secured to a top plate 28 and a bottom or base plate 29. Each of these plates is formed in any suitable. manner for co-operation with locating elements on the multi-feed circular knitting machine, so that the blocks can, as units, be simply pushed into position or withdrawn from the machine. Thus, in the specific illustrated example applied to a machine of the rotary needle cylinder type, the underside of the bottom or base plate 29 of each slotted block 18 is recessed as at 29a to enable it to be engaged with upstanding locating pins 30, 31 on the fixed bed plate 17 of the machine. On the other hand, the upper surface of the top'plate 28 of each slotted block 18 is so contoured and recessed as at 28a (FIG. 3) as to enable it to receive the lower end of a downwardly urged locating pin 32 mounted in the fixed cambox plate 33 of the machine.

In any event, the upper and lower edges of each toothed programme comb 24 is formed with small protuberances 34 adapted to be slid into recesses (not shown) formed in the backs of the top and the bottom or base plates 28 and 29 of the corresponding slotted block, these protuberances' 34 being pushed fully home up to the inner ends of the said recesses so that the comb is located in a vertical position with its teeth 24a and 24b extending horizontally.

Each slotted block 18 may, if desired, be of laminated form assembled from a plurality of relatively thin and substantially rectangular laminates 35 (see FIGS. 3, 7, 8 and 9) of any suitable plastics material each having formed in its upper surface recesses appropriately shaped to receive a pair of jack selector slides 19, 20, including their tails TP,'and also the small compression springs'2l for urging the slides forwardly, the slides and the springs in each laminate 35 being retained in position by the flat underside of the next laminate above which covers the recesses and thus completes the housing for the said slides'and springs. In fact, the recesses, by this mode of assembly are converted into slots. Each of the laminates has holes 36 formed throughits four corners to enable it to be located upon four tie rods such as 36. Thus, to produce a complete block 18, laminates 35 (with their slides 19, 20 and springs 21 fitted therein) are successively engaged with the tie rods and assembled one on top of the other to provide a vertical bank of the laminates. Also fitted upon the opposite ends of the tie rods 36 are the aforementioned top and bottom or base plates 28 and 29 which are of steel. The ends of the tie rods are threaded to receive retaining nuts (not shown). The laminated assembly is compressed under great pressure and finally welded to gether to produce what is, in effect, a manually settable selection unit.

Each such unit 18 is provided with a levelling cam 37 for action downwardly upon the top edges of levelling butts 38 one of which is provided at or near the lower end of each of the pattern jacks 13. Thus, after a selection of these jacks 13 by the selection unit 18 in advance of each knitting station, the raised jacks are restored to a common low level, by the levelling cam 37 on the next selection unit, in readiness for re-selection.

If desired, means may be provided to cancel the predetermined jack selection normally effected by any one of the selection units 18 by instead raising all of the jacks at that unit to the height at which the corresponding needles clear and knit. To this end there is provided, in the illustrated example, adjacent to the lower end of each selection unit 18 a movable all-knit cam 39 which is adapted, when raised into its operative position, to act on the lower edges of the levelling butts 38 of all of the passing pattern jacks 13 to raise the latter The invention provides the possibility of patterning on finer gauges since at each point of jack selection there are less pattern jacks per inch in the separate jack cylinder than there are needles per inch in the needle cylinder: for this reason more room is provided circumferentially for picking out individual pattern jacks.

Moreover, since the 'pairs of tuck and knit slides 19, 20 in any one slotted block 18 function at a confined location, the actual extent of the circumferential space in which jack selections in advance of any one knitting station are made is reduced to a minimum. This, in fact, compares very favourably with a patterning system in which, say, pressers require to be pressed in at one point to prepare jacks for lifting at a later point. Accordingly, since there is a substantial saving in circumferential space, a machine to which the invention is applied can have an increased number of feeds.

We claim: .1. In a multi-feed circular knitting machine having a needle cylinder; needles operable in said cylinder; a set of corresponding pattern jacks furnished with patterning butts, and jack selector slides for action selectively upon the said butts for the purpose of exercising selective individual control over the needles, a patterning mechanism of the form including a separate tricked jack cylinder accommodating said pattern jacks, said jack cylinder being co-axial with, but of a larger diame-' ter than, the needle cylinder and the patterning butts on the jacks being set out in diagonal lines but with the vertical pitch of said butts reduced to such an extent that lifting movements imparted to the pattern jacks by action upon their butts of the prearranged pattern slides are less than sufficient to raise the corresponding needles to the heights required; levers for transmitting to the needles, and simultaneously amplifying, the lifting movements imparted to the pattern jacks by the slides; and slotted blocks each for accommodation of a vertical bank of jack selector slides in each of which blocks the selector slides are arranged in superimposed pairs respectively opposite the planes of the patterning butts, with the two slides of each pair disposed side by side and constituting tuck and knit slides with operative noses having cam faces upwardly sloping to respectively different extents heightwise, the said patterning mechanism being characterised in that springs within the slotted blocks urge the jack selector slides into their selected positions but against the biassing influence of which springs the slides are withdrawable to inoperative positions clear of the patterning butts in the relevant planes, and also in that there is inserted in each slotted block a removable toothed programme comb having predetermined ones of its teeth reduced in length and other wholly broken off according to pattern requirements, whereby depending on whether a full length tooth, a tooth of reduced length or a gap in the comb produced by wholly breaking off a tooth is presented adjacent to abutments on a pair of jack selector slides, the corresponding pattern jacks with patterning butts at that level will either not be raised, or only partly raised or fully raised to cause the relevant needles to miss, tuck or knit respectively.

2. A patterning mechanism according to claim 1, wherein the butts on the jacks are set out in a multiplicity of superimposed horizontal planes equally spaced apart heightwise a distance equivalent to the vertical pitch of the butts.

3. A patterning mechanism according to claim 1, wherein each tuck slide is provided with a lateral projection arranged to move within an elongated recess formed in the adjacent side of the companion knit slide, the said lateral projection being arranged to abut against the forward ends of tail portions of bothslides.

4. A patterning mechanism according to claim 1, wherein at least the major portions of the jack selector slides are disposed in superimposed horizontal planes, the operative noses of the slides being located at their inner ends and the upwardly sloping cam faces of the each such slide having a main front portion which together with its operative cam-like nose, protrudes through the front of the relevant slotted block and a slim tail portion which protrudes rearwardly through the back of the said block.

6. A patterning mechanism according to claim 3, wherein the tail portion of each slide is provided with an abutment for contact, as required according to the pattern, with the back of a tooth at the relevant height on a programme comb whereby the slide is held back in its withdrawn position.

7. A patterning mechanism according to claim 6, wherein an outer margin of the tail portion of each slide is slit longitudingally and bent out of the plane of the slide to provide the abutment.

8. A patterning mechanism according to claim 6, wherein the tail portions of all of the tuck and knit slides are recessed for reception of a tool by means of which all of the superimposed pairs of slides in any one slotted block can be simultaneously withdrawn to their inoperative positions and held there whilea programme comb is inserted into position at the back of the block immediately in front of the abutments on the slides, whereby after removal of the tool slides whose abutments are opposite gaps in the comb are enabled to move forward into their operative positions, whereas the slides having abutments opposite full teeth or parts of teeth on the comb are held back in their inoperative positions.

9. A patterning mechanism according to claim 1, wherein each programme comb initially has thereon a full complement of full length teeth corresponding in number to the pairs of slides in the corresponding slotted block, each tooth being notched at its root and substantially half way along its length to facilitate easy and selective breakage of teeth, according to patterning requirements.

10. A patterning mechanism according to claim 9, wherein any full length tooth holds back in their inoperative positions the tuck and knit slides at that level; a gap in the cg rnbpermits both slides of the pair at that level to move into their operative positions; and any half tooth on said comb holds back the knit slide and permits only the tuck slide at the relevant level to move into its operative position.

11. A patterning mechanism according to claim 1, wherein each slotted block is interposed between and rigidly secured to a top plate and a base plate each of such plates being formed for co-operation with locating elements on the circular knitting machine so that the blocks can, as units, be simply pushed into position or withdrawn from the machine.

12. A patterning mechanism according to claim 11, wherein each slotted block is of laminated form assembled from a plurality of thin and rectangular laminates of plastics material each having openings formed in its corners and recesses in its upper surface to receive one pair of the tuck and knit jack selector slides and also the springs for urging these slides forwardly, said springs being compression springs and the slides and the springs in each laminate being retained in position by the flat underside of the next laminate above which covers the recesses and completes the housing for said slides and springs, tie rods extending through the holes and through the top and base plates and the whole assemblage being compressed and welded together.

13. A patterning mechanism according to claim 1, wherein each slotted block is provided with a levelling cam for action downwardly upon the top edges of levelling butts one of which is provided on each of the pattern jacks, whereby after a selection of these jacks in advance of each knitting station the raised jacks are restored to a common low level by the levelling cam on the next slotted selection block, in readiness for reselection.

14. A patterning mechanism according to claim 1, which includes means for cancelling the predetermined jack selection normally effected by any one of the slotted blocks and instead raising all of the jacks at that block to the height at which the corresponding needles clear and knit.

15. A patterning mechanism according to claim 13, wherein there is associated with each slotted block a movable all-knit cam which is adapted when moved into its operative position by a manually operable actuator, to act on the lower edges of the levelling butts of all the passing pattern jacks to raise the latter to knit height. 

1. In a multi-feed circular knitting machine having a needle cylinder; needles operable in said cylinder; a set of corresponding pattern jacks furnished with patterning butts, and jack selector slides for action selectively upon the said butts for the purpose of exercising selective individual control over the needles, a patterning mechanism of the form including a separate tricked jack cylinder accommodating said pattern jacks, said jack cylinder being co-axial with, but of a larger diameter than, the needle cylinder and the patterning butts on the jacks being set out in diagonal lines but with the vertical pitch of said butts reduced to such an extent that lifting movements imparted to the pattern jacks by action upon their butts of the prearranged pattern slides are less than sufficient to raise the corresponding needles to the heights required; levers for transmitting to the needles, and simultaneously amplifying, the lifting movements imparted to the pattern jacks by the slides; and slotted blocks each for accommodation of a vertical bank of jack selector slides in each of which blocks the selector slides are arranged in superimposed pairs respectively opposite the planes of the patterning butts, with the two slides of each pair disposed side by side and constituting tuck and knit slides with operative noses having cam faces upwardly sloping to respectively different extents heightwise, the said patterning mechanism being characterised in that springs within the slotted blocks urge the jack selector slides into their selected positions but against the biassing influence of which springs the slides are withdrawable to inoperative positions clear of the patterning butts in the relevant planes, and also in that there is inserted in each slotted block a removable toothed programme comb having predetermined ones of its teeth reduced in length and other wholly broken off according to pattern requirements, whereby depending on whether a full length tooth, a tooth of reduced length or a gap in the comb produced by wholly breaking off a tooth is presented adjacent to abutments on a pair of jack selector slides, the corresponding pattern jacks with patterning butts at that level will either not be raised, or only partly raised or fully raised to cause the relevant needles to miss, tuck or knit respectively.
 2. A patterning mechanism according to claim 1, wherein the butts on the jacks are set out in a multiplicity of superimposed horizontal planes equally spaced apart heightwise a distance equivalent to the vertical pitch of the butts.
 3. A patterning mechanism according to claim 1, wherein each tuck slide is provided with a lateral projection arranged to move within an elongated recess formed in the adjacent side of the companion knit slide, the said lateral projection being arranged to abut against the forward ends of tail portions of both slides.
 4. A patterning mechanism according to claim 1, wherein at least the major portions of the jack selector slides are disposed in superimposed horizontal planes, the operative noses of the slides being located at their inner ends and the upwardly sloping cam faces of the operative noses of each pair of tuck and knit jack selector slides being complementary.
 5. A patterning mechanism according to claim 4, wherein apart from the complementary form of their operative camlike noses the jack selector slides of each pair are respectively left-handed and right-handed, each such slide having a maIn front portion which together with its operative cam-like nose, protrudes through the front of the relevant slotted block and a slim tail portion which protrudes rearwardly through the back of the said block.
 6. A patterning mechanism according to claim 3, wherein the tail portion of each slide is provided with an abutment for contact, as required according to the pattern, with the back of a tooth at the relevant height on a programme comb whereby the slide is held back in its withdrawn position.
 7. A patterning mechanism according to claim 6, wherein an outer margin of the tail portion of each slide is slit longitudingally and bent out of the plane of the slide to provide the abutment.
 8. A patterning mechanism according to claim 6, wherein the tail portions of all of the tuck and knit slides are recessed for reception of a tool by means of which all of the superimposed pairs of slides in any one slotted block can be simultaneously withdrawn to their inoperative positions and held there while a programme comb is inserted into position at the back of the block immediately in front of the abutments on the slides, whereby after removal of the tool slides whose abutments are opposite gaps in the comb are enabled to move forward into their operative positions, whereas the slides having abutments opposite full teeth or parts of teeth on the comb are held back in their inoperative positions.
 9. A patterning mechanism according to claim 1, wherein each programme comb initially has thereon a full complement of full length teeth corresponding in number to the pairs of slides in the corresponding slotted block, each tooth being notched at its root and substantially half way along its length to facilitate easy and selective breakage of teeth, according to patterning requirements.
 10. A patterning mechanism according to claim 9, wherein any full length tooth holds back in their inoperative positions the tuck and knit slides at that level; a gap in the comb permits both slide of the pair at that level to move into their operative positions; and any half tooth on said comb holds back the knit slide and permits only the tuck slide at the relevant level to move into its operative position.
 11. A patterning mechanism according to claim 1, wherein each slotted block is interposed between and rigidly secured to a top plate and a base plate each of such plates being formed for co-operation with locating elements on the circular knitting machine so that the blocks can, as units, be simply pushed into position or withdrawn from the machine.
 12. A patterning mechanism according to claim 11, wherein each slotted block is of laminated form assembled from a plurality of thin and rectangular laminates of plastics material each having openings formed in its corners and recesses in its upper surface to receive one pair of the tuck and knit jack selector slides and also the springs for urging these slides forwardly, said springs being compression springs and the slides and the springs in each laminate being retained in position by the flat underside of the next laminate above which covers the recesses and completes the housing for said slides and springs, tie rods extending through the holes and through the top and base plates and the whole assemblage being compressed and welded together.
 13. A patterning mechanism according to claim 1, wherein each slotted block is provided with a levelling cam for action downwardly upon the top edges of levelling butts one of which is provided on each of the pattern jacks, whereby after a selection of these jacks in advance of each knitting station the raised jacks are restored to a common low level by the levelling cam on the next slotted selection block, in readiness for re-selection.
 14. A patterning mechanism according to claim 1, which includes means for cancelling the predetermined jack selection normally effected by any one of the slotted blocks and instead raising all of the jacks at that block to the height at which the correspondiNg needles clear and knit.
 15. A patterning mechanism according to claim 13, wherein there is associated with each slotted block a movable ''''all-knit'''' cam which is adapted when moved into its operative position by a manually operable actuator, to act on the lower edges of the levelling butts of all the passing pattern jacks to raise the latter to knit height. 